Instead, blame your genome. Scientists have discovered a gene that may regulate how much people sleep.

According to ABC, German scientists have found that people with two copies of a gene called ABCC9 slept less than those with one or no copies. ScienceDaily clarifies that the study was conducted "in an undisturbed environment," presumably meaning subjects got to sleep as long as they wanted and weren't awakened by children or cats or the giant metal-eating monsters that come out at 5 AM on the street outside my apartment. Folks with two copies of ABCC9 can presumably get a lot done while the rest of us are either sleeping or blearily fantasizing about inserting caffeine directly into our eyes, but there's a downside: the gene is also linked to diabetes and heart disease. Study author Karla Allebrandt says, "Apparently, the relationships of sleep duration with other conditions, such as heart disease and diabetes, can be in part explained by an underlying common molecular mechanism."

Still, Dr. Mark Mahowald of the Minnesota Regional Sleep Disorders Center implies that the study should make people feel better about their sleep needs: "Our society has equated sleepiness with defects of character, like laziness and depression, but really, some people are generally sleepier during the day. We have to accept the fact that sleep duration is genetically determined and not a sign of a defect." So next time someone accuses you of being a bum because you went back to bed in the middle of the day, just tell them you're probably missing an ABCC9 — and if that person is your mom or dad, you can blame them.